Some modern vehicles are equipped with one or more systems which allow the vehicle to be arranged into a semi-autonomous and/or autonomous drive mode. Such systems may include predictive safety systems, adaptive cruise control systems, lane-departure warning systems, navigation systems, communication systems and/or automatic brake control systems. Some of the systems may monitor the vehicle surroundings in order to control a host vehicle position relative a road on which the host vehicle drives, and may further determine positions and/or velocities of surrounding objects, such as other vehicles, pedestrians and various obstacles. Such systems may calculate whether a collision between the host vehicle and other vehicles or objects is imminent, and may in such case calculate an alternative route, and/or warn a driver of the host vehicle.
In order to collect information regarding the host vehicle surrounding, the host vehicle is generally equipped with various sensors that monitor the host vehicle surrounding. Such sensors may include one or more cameras, radar-units and/or lidar-units.
In addition to the sensors, a communication system in the host vehicle may be arranged to communicate with one or more external communication arrangements, such as remote servers/clouds, other vehicles and/or roadside units. The host vehicle may receive information on e.g. available routes, obstacles and traffic information via the communication arrangement.
In order to provide autonomous drive functions, the host vehicle or systems thereof depends on the information received through the sensors and/or the communication arrangement. If one or more of the sensors become unavailable, or if the communication between the host vehicle and external communication arrangements is interrupted, some or all autonomous drive functions may be disabled. A driver may then need to operate the vehicle, or some vehicle functions, manually.
If a sensor or communication-link becomes unavailable, the autonomous vehicle may be configured to stop. In some cases the driver may have to operate the vehicle manually with short notice. Both unplanned stops of the autonomous vehicle and a short preparation time for manual driving may be annoying and/or stressful for the driver.
Improvements related safety and/or comfort during autonomous driving are therefore desirable.